Depend on nexmo/github-actions@main

Author: mheap

.github/workflows/push.yml

@@ -9,7 +9,7 @@ jobs:
  runs-on: ubuntu-latest
  steps:
  - name: Update NDP Submodule
- uses: nexmo/github-actions/submodule-auto-pr@master
+ uses: nexmo/github-actions/submodule-auto-pr@main
  env:
  GH_ADMIN_TOKEN: ${{ secrets.PDX_GH_TOKEN }}
  PR_ACTIVE_BRANCH: master